“I am interested in understanding and predicting how microbial communities influence interactions between plants and insects,” she said. “In the Vannette lab (in Briggs Hall), we use tools and concepts from microbial ecology, chemical ecology, and community ecology to better understand the ecology and evolution of interactions among plants, microbes and insects."
A native of Hudsonville, Mich., Vannette received her bachelor of science degree in biology with honors at Calvin College, Grand Rapids, Mich., and her doctorate in ecology and evolutionary biology from the University of Michigan, in 2011. Her dissertation was entitled “Whose Phenotype Is It Anyway? The Complex Role of Species Interactions and Resource Availability in Determining the Expression of Plant Defense Phenotype and Community Consequences.”
In her PhD research, she examined how variation in nutrient availability and plant associations with mycorrhizal fungi belowground influenced defense chemistry in milkweed plants and the performance of a specialist herbivore (Danaus plexippus). She found that resource-based tradeoffs can in part explain plant allocation to antiherbivore defense and mycorrhizal fungi. This work also describes that plant genotypes vary in their investment in defense and associations with belowground fungi.
As a Stanford University postdoctoral fellow, funded by a life sciences research fellowship, Vannette examined the community ecology of plant-associated microorganisms. Using diverse systems, she studied the assembly of microbial communities, microbial response to anthropogenic changes like habitat fragmentation, and microbial effects on plant-pollinator interactions.
- Community ecology of plant-associated microbial communities. She explored what mechanisms shape the structure and function of microbial communities associated with plants, and how to assemble mechanisms to better understand functions, including the effects on insect herbivores and pollinators. She also researched how ants influence microbial community structure and nectar characteristics in coffee agroecosystems.
- Nectar ecology. Knowing that yeasts and bacteria are common inhabitants of flowers, and attain high densities in floral nectar, she researched how these microbes influence plants and pollinators, the mechanisms involved, and evolutionary ecology of these interactions. She also studied how nectar constituents influence pollinator foraging and health.
- Influence of anthropogenic changes on plant-microbe (insect) interactions. She researched how fragmentation affects fungal community composition in the rhizosphere of Meterosideros polymorpha, a species of flowering evergreen tree in the myrtle family. She also studied elevated carbon dioxide changes plant-microbe-insect interactions, and researched the effects of mycorrhizal fungi on plant defense and plant-herbivore interactions.
The National Wildlife Research Foundation featured Vannette's research on monarchs and milkweed in its March 11, 2013 piece on “Catering to Butterfly Royalty." The article, by author Doreen Cubie, focused on Vannette's research as a graduate student at the University of Michigan. Vannette and advisor Mark Hunter studied five common species of milkweeds, the host plant for monarchs. They found that climate change may disrupt the chemistry of milkweeds, and encouraged gardeners to help the monarchs by planting more of these critical host plants.
Vannette and Hunter grew the plants in open-air chambers, “exposing them to elevated amounts of carbon dioxide designed to mimic Earth's atmosphere in the future,” wrote Cubie. “Although most of the plants grew slightly larger, the composition of plant leaves changed dramatically. Most of the milkweed families decreased their production of toxins, some by as much as 50 percent. The extra carbon dioxide exposure toughened the leaves, a problem for the caterpillars.
Last March Vannette was an invited speaker on the ecology and evolution of the microbiome at the University of Michigan Early Career Scientists' symposium in Ann Arbor, Mich.
Among her recent publications:
- Co-author of “Plant-Derived Variation in the Composition of Aphid Honeydew and its Effects on Colonies of Aphid-Tending Ants,” published in November 2014 in the journal Ecology and Evolution.
- Lead author of “Genetic Variation in Plant Below-Ground Response to Elevated CO2 and Two Herbivore Species,” published in July 2014 in Plant Soil.
- Co-author of “Honey Bees Avoid Nectar Colonized by Three Bacterial Species, but not by a Yeast Species, Isolated from the Bee Gut,” published in a January 2014 edition of PLOS ONE.
- Lead author of “Historical Contingency in Species Interactions: Towards Niche-Based Predictions,” published November 2013 in Ecology Letters. (Recommended by the Faculty of 1000)
De los Santos, 45, joined the UC Davis administration in July 2015 following a 22-year military career.
“Faculty, staff and students in the Department of Entomology and Nematology are deeply saddened by the death of Chris John de los Santos,” said Michael Parrella, professor and chair of the department. “Chris had been with us for a short period of time, but he was already making some profound changes in how the department was managed. Chris was a disciplined, critical thinker and his strength was in developing strategic and business plans – areas where there was a real need in the department.”
“Chris was liked and respected by all associated with the Phoenix Cluster,” Parrella said. “Chris put the Department of Entomology and Nematology on a trajectory that will make us better in the research, teaching and outreach that we do. We will continue to follow the path that he has laid out for us. We will never forget his contributions. Our condolences go out to his family as they try and cope with this tragic loss.”
A remembrance will be held at a later date, Parrella said.
Said Lynn Kimsey, director of the Bohart Museum of Entomology, professor of entomology and former interim chair of the department: “Chris had terrific management and leadership skills. He was the kind of person everyone liked to work with, personable yet business-like.”
“Chris made amazing contributions to the department in a very short period of time,” said Executive Committee member Larry Godfrey, Extension entomologist. “He had many strengths but the two I was most impressed with were his ability to analyze situations and make logical, thoughtful recommendations and his propensity to want to contribute to the betterment of humankind. He often stated that he enjoyed working in the department and at UC Davis because he was confident we were making a difference in people's lives. Although not a person to ‘accept credit,' Chris clearly contributed to this mission of the department.”
“During his short time in the department, Chris was already making important contributions and bringing a high level of professionalism and strategic thinking to our efforts,” said entomology professor and Executive Committee member Jay Rosenheim.
“Chris radiated integrity, decency and respect,” said James R. Carey, distinguished professor of entomology. “He was one of the most progressive and responsive staff members whom I had the pleasure to know in my 35 years at UC Davis.”
At UC Davis, de los Santos managed the two departments' budgets, encompassing a total of $30.5 million, including federal and state monies, and 450 personnel. He provided leadership, oversight and management for the Phoenix Cluster. He administered or oversaw the areas of business and finance, extensive contract and grant administration, academic and staff human resources, teaching and instructional support, information technology, space utilization, and research and teaching laboratory support needs.
An accomplished military veteran with more than 22 years of extensive logistics experience in the Department of Defense, de los Santos moved to Davis with his family after serving as executive director/commander of the 673rd Logistics Readiness Group at Joint Base Elmendorf-Richardson, Alaska, where he led a workforce of 575 with a $12 million budget in support of the Department of Defense's sole joint base logistics group.
He was known as a proven leader, team player, mentor and motivator with the ability to simultaneously manage multiple projects, delivered on time and exceeding expectations. He served in major leadership roles at his tours of duty in Anchorage, Alaska; San Antonio, Texas; Santa Monica, Calif.; the Pentagon in Washington, D.C.; Lackland Air Force Base, Texas; and Vandenberg Air Force Base, Calif., and also at the Al Dhafra Air Base, United Arab Emirates, U.S. Embassy, Sultanate of Oman; and at the Incirlik Air Base, Turkey, among others.
De los Santos received his bachelor's degree in marine transportation in 1992 from the U.S. Merchant Marine Academy, Kings Point, N.Y.; his master of science degree in international relations, Troy State University, Troy, Ala. in 1998; and his master degree in military operational art and science from Air University, Maxwell Air Force Base, Ala., in 2006. His career also included serving as an assistant professor of aerospace studies at the University of Portland, Ore., from 1998 to 2000.
During his military career, de los Santos directed distribution management, matériel management, contingency operations, fuels management, airlift operations, and vehicle management. He planned and programmed logistics support for wartime requirements and led workforce development for the Logistics Readiness Officer (LRO) career field.
A resident of Davis, Judson served as a faculty member of the UC Davis Department of Entomology (now UC Davis Department of Entomology and Nematology) for 30 years, from 1961 until his retirement in 1991.
"The Department of Entomology and Nematology lost one of its pillars with the passing of Dr. Judson," said Michael Parrella, professor and chair of the department. "Although the department's national and international reputation is based on the work of current faculty, it cannot be denied the prestige of the department can also be attributed to our retired faculty. It sounds clichéd, but we are standing on the shoulders of giants and Dr. Judson was one of these. Dr. Judson continued to be an active member of the department -- coming regularly to our seminars and participating in social events. Up until a few years ago, he helped teach our core course in Insect Physiology. Charlie Judson's contributions to the science of entomology and to the department will never be forgotten."
Born Oct 21, 1926 in Lodi, Calif., Charles grew up on a ranch in Riverside, where he developed and nurtured his passion for the outdoors, nature, science and animals. He enlisted in the U.S. Navy during World War II, serving on the USS Wichita.
He received his bachelor of science degree in zoology from UC Santa Barbara in 1950, and his doctorate in entomology from UC Berkeley in 1954. He and his wife, Marilyn, and family moved to Davis in 1958 when he accepted a position with the California Department of Public Health. He joined the UC Davis faculty in 1961 as an insect physiologist professor. He was a 35-year member of the Entomological Society of America.
“Our family quickly learned not to be afraid of insects, but to respect them in our environment,” recalled Jan. “We don't squish most bugs, but put them outside.”
“Charles enjoyed his work as a researcher and student advisor and often would invite students to his home, maintaining lifelong relationships,” Marilyn said.
Professor Judson launched the career of many PhD students; he inspired them to better understand insect behavior by investigating insect physiological control mechanisms
Emeritus entomology professor Robert Washino, former department chair and former associate dean, UC Davis College of Agricultural and Environmental Sciences, recalled that “Charles Judson was one of the newcomers who among others--Professors Norman Gary, George McClelland, Donald McLean-- joined the department in the early sixties and introduced greater emphases on physiology and behavior into the teaching and research program that previously stressed taxonomy and regulatory entomology.”
“Charles was one of the first faculty members in the department to be awarded a National Institutes of Health grant for his work on mosquito egg physiology,” Washino said. “I believe Charlie's calm and deliberate manner of successfully carrying out his teaching, research and public service made him a most valuable member of the department. One of Charlie's most productive graduate students, Henry Hagedorn, went on to make major contributions in mosquito reproductive physiology at the University of Arizona at Tucson.”
Many of Professor Judson's colleagues praised him as an excellent scientist and wonderful friend. Said distinguished professor of entomology James R. Carey: "Charlie Judson radiated graciousness, trust and respect, and personified everything good in a university scientist, mentor, and teacher. He not only helped shape our department in its early days, but also set a very high bar for personal decency and professional integrity. Colleagues like Charlie are hard to find, difficult to lose, and impossible to forget."
Albert Grigarick, UC Davis emeritus professor of entomology, said “Charlie was a friend, colleague, and neighbor for nearly 50 years. He was always willing to help you in your academic endeavors or backyard projects. He will be missed by the many students that sought his scientific knowledge and friendly advice.”
Former graduate student Tom Batchelor. who focused his research on the nature of physiological lesions in insects caused by radiation, was Professor Judson's last graduate student. “Gaining control of mosquitoes to reduce their impact on human health has been at the heart of many research programs for decades,” said Batchelor, who now lives in New Zealand. “Professor Judson's research contributed to a better understanding of specific aspects of their feeding and oviposition behavior, and the physiological control mechanisms underpinning this behavior.”
Throughout his academic career, Professor Judson focused his research on the stimuli that caused mosquito eggs to hatch. “Using the eggs of Aedes aegypti and A. nicromaculis, he found that mosquito eggs in water under low oxygen conditions hatched readily,” Batchelor said. “Just the act of decreasing the oxygen concentration, and not just a low oxygen concentration itself, proved to be a powerful hatching stimulus. He also examined the ability of various compounds to penetrate the egg of the mosquito, since mosquito eggs are rather impermeable to water and several chemicals. His research on the ovicidal qualities of these compounds led to further research on better ways to control mosquitoes at the egg stage.”
Another aspect of his research explored the physiological basis underlying a mated female's predisposition to oviposit. Professor Judson showed oviposition was stimulated by a “biochemical signal” emitted by the accessory gland of the male mosquito, Batchelor pointed out. “Virgin females tend to retain their eggs and not oviposit, but they will oviposit if a male accessory gland is implanted into them. Similarly, Professor Judson showed that mosquito biting behavior coincided with the terminal phases of each egg cycle, and that fewer mated females fed at these times than virgin females.”
As an aside, Batchelor said he sometimes saw Professor Judson feeding his laboratory mosquitoes by putting his whole arm in their cage—“when the hamster was having a day off.” Professor Judson commented that feeding the mosquitoes this way was not putting his health at risk, “but rather the health of the mosquitoes exposed to low levels of nicotine and alcohol residues in his blood!” Batchelor recalled.
Entomologist Fran Keller, who served as Professor Judson's teaching assistant for his insect physiology class while working toward her doctorate in entomology, recalled that “Charlie was always happy to see students. At the Department of Entomology's barbecues, I remember how he would make the rounds and make sure he talked with all the students. My interactions with him as a TA for insect physiology were always informative, relaxed and positive. He enjoyed teaching and sharing his knowledge with students. He was a thoughtful, caring and compassionate mentor.”
“Charlie also served on my oral exam committee,” Keller said. “He had a way of confronting you with questions that made you think. As a mentor, that is what you are supposed to do. As a physiologist, he asked me, ‘Why do you want to work so hard on beetles doing a revision when somebody is just going to come along and change it all around in 50 years? You taxonomists always seem to be changing names,' and as a taxonomist I answered, ‘Well, if I do it correctly, then changes will be made when there are new discoveries, so I am providing a foundation for future work.' And he replied, 'Okay that makes sense.' He wanted students to think about their future and what they were doing. To say Charlie was concerned for and kind to his students would be an understatement. I am very saddened by his passing and I will miss his presence as a friend and mentor.”
In addition to his teaching and research, Professor Judson was actively involved in the community, working with Habitat for Humanity, Yolo County Court Appointed Special Advocates (CASA), Yolo County Grand Jury, Yolo Family Service Agency, Sierra Club, Short-Term Emergency Aid Committee (STEAC), Senior Learning Unlimited and All Things Right and Relevant.
His other interests included politics, gardening, photography, woodworking and the building of wooden boats. He and his family spent many hours on Loon Lake, the Sierras, in his hand-built vessels, including kayaks, canoes and dinghies. His involvement with the Traditional Small Craft Association, his family said, “led to wonderful friendships, as well as involvement in Seeds of Learning, through which he spent several summers in El Salvador.”
His parents met on the UC Davis campus when both were students at UC Berkeley and were required to spend a year at “The Farm” because of their major. His father help plant the black walnuts on Russell Boulevard.
At his request, no memorial service will be held. The family will gather during the holidays to scatter his ashes in Monterey Dunes, sharing fond memories of beachcombing, digging holes in the sand, and just being together as a close-knit family.
Professor Judson was a strong believer in “walking the walk” by acting on his integrity and beliefs, his family said. In lieu of flowers, he would ask that people “pay it forward” by reaching out to another person or group.
That's the topic of a special conference--open to the public –set from 10 a.m. to 4 p.m., Wednesday, Sept. 9 at the UC Davis Conference Center, 550 Alumni Lane. UC Davis researchers and state officials will address the crowd, announced conference coordinator Dave Fujino, director of the UC Davis-based California Center for Urban Horticulture.
“We are pleased to have such a knowledgeable lineup of UC Davis researchers who will clarify the issue of impact of neonicotinoid impacts on pollinators by summarizing and presenting the past and current science-based research,” Fujino said. “We are also fortunate to have additional presentations on the regulation guidelines on neonicotinoids and their role in controlling invasive pests in California, and a diverse group of stakeholders participating in a panel discussion on the neonicotinoid issue.”
Neonicotinoids, recently implicated in the worldwide die-off of pollinators, including honey bees, are a class of neuro-active insecticides chemically similar to nicotine. Considered important in the control of many significant agricultural and veterinary pests, they target the central nervous system of insects, resulting in paralysis and death. “Neonics,” as they're called, are commonly used on farms, and around homes, schools, and city landscapes.
Michael Parrella, professor and chair of the UC Davis Department of Entomology, will provide an overview of the current use of neonicotinoids and the role of honey bees in California agriculture. Six other speakers are scheduled, along with a panel discussion.
The speakers include:
- Brian Leahy, director of the California Department of Pesticide Regulation, who will discuss “California Pesticide Regulation of Neonicotinoids”
- Nick Condos, director of the Plant Health and Pest Prevention Services Division, California Department of Food and Agriculture, “Neonicotinoid Risks Associated with Invasive Species Management”
- Karen Jetter, associate project economist, UC Agricultural Issues Center, “Trends in Neonicotinoid Usage in California Agriculture and the Control of Invasive Species”
- Margaret “Rei” Scampavia, a doctoral candidate who studies with major professors Neal Williams and Ed Lewis of the UC Davis Department of Entomology and Nematology, “Past Neonicotinoid and Bee Research”
- Elina Lastro Niño, Extension apiculturist based at the Harry H. Laidlaw Honey Bee Research Facility, UC Davis, “Current Neonicotinoid and Bee Research.”
The California Center for Urban Horticulture (CCUH) will co-host the event with the UC Davis Department of Entomology and Nematology and the UC Agriculture and Natural Resources.
Sponsors include California Association of Nurseries and Garden Centers (CANGC), a trade organization founded in 1911 to promote and protect the California nursery industry; Four Winds Growers, based in Winters, Calif.; Scotts Miracle-Gro, a company headquartered in Marysville, Ohio, and known as the world's largest marketer of branded consumer lawn and garden products; and Monrovia, a horticultural craftsmen company headquartered in Azusa, Calif.
At the close of the conference, Fujino will preside over a panel discussion on neonicotinoid issues and concerns. Questions and answers from the audience will follow. The panel is to include a UC Cooperative Extension farm advisor, and representatives from the California Association of Nurseries and Garden Centers, Home Depot, Scotts Miracle-Gro, Bayer CropScience and the American Beekeeping Federation.
The registration fee of $50 will include lunch, as well as the post-conference social hour. To register, access the CCHU website at http://ccuh.ucdavis.edu/public/copy_of_public/neonicotinoid-pollinator-conference-2015/neonic or contact CCUH representative Kate Lincoln at email@example.com or (530) 752-6642.
The European Union recently adopted a proposal to restrict the use of three pesticides belonging to the neonicotinoid family (clothianidin, imidacloprid and thiametoxam) for a period of two years. In addition, the U.S. Fish and Wildlife Service announced that by January 2016, it will ban the use of seeds treated with neonicotinoid pesticides and the use of crops improved through biotechnology throughout the 150 million acres managed by the National Wildlife Refuge System.
So says ecologist Richard Karban, professor of entomology in the UC Davis Department of Entomology and Nematology, in his newly published book, Plant Sensing and Communication (University of Chicago Press).
The 240-page book is a “landmark in its field,” said Graeme Ruxton of the University of St. Andrews, UK, co-author of Experimental Design for the Life Sciences and Plant-Animal Communication.
The book is “the first comprehensive overview of what is known about how plants perceive their environments, communicate those perceptions, and learn,” according to the publisher. “Facing many of the same challenges as animals, plants have developed many similar capabilities: they sense light, chemicals, mechanical stimulation, temperature, electricity, and sound. Moreover, prior experiences have lasting impacts on sensitivity and response to cues; plants, in essence, have memory."
Added the publisher: “Nor are their senses limited to the processes of an individual plant: plants eavesdrop on the cues and behaviors of neighbors and—for example, through flowers and fruits—exchange information with other types of organisms. Far from inanimate organisms limited by their stationary existence, plants, this book makes unquestionably clear, are in constant and lively discourse.”
What are 10 things to know about plant sensing and communication? According to Karban:
- Plants sense their environments and respond.
- Although they lack central nervous systems, they process information and appear to "behave intelligently."
- They sense the position of competitors and "forage" for light.
- They sense the availability of water and nutrients in the soil and "forage" for these resources.
- Their decisions are influenced by past experiences, akin to memory.
- The respond to reliable cues that predict future events, allowing them to "anticipate."
- Plants respond differently to cues that they themselves produce, allowing them to distinguish self from non-self.
- They respond differently to close relatives and strangers.
- Plants that are prevented from sensing or responding experience reduced fitness.
- By understanding the "language" of plant responses, we can grow healthier and more productive plants.
Karban has researched plant communication in sagebrush (Artemisia tridentata) on the east side of the Sierra since 1995. His groundbreaking research on plant communication among kin, published in February 2013 in the Proceedings of the Royal Society B: Biological Sciences, drew international attention. In that study, Karban and his co-researchers found that kin have distinct advantages when it comes to plant communication, just as “the ability of many animals to recognize kin has allowed them to evolve diverse cooperative behaviors.”
“Plants responded more effectively to volatile cues from close relatives than from distant relatives in all four experiments and communication reduced levels of leaf damage experienced over the three growing seasons,” they wrote.
In other words, if you're a sagebrush and your nearby kin is being eaten by a grasshopper, deer, jackrabbit, caterpillar or other predator, communication is more effective if you're closely related. Through volatile cues, your kin will inform you of the danger so you can adjust your defenses.
Karban likened this kind of plant communication to eavesdropping.” Plants “hear” the volatile cues of their neighbors as predators damage them.
The most basic form of communication? When a plant is being shaded, it senses the diminished light quality caused by a competitor and responds by moving away, Karban says.
“Plants are smart,” wrote Adrian Barnett of New Scientist in reviewing the book. “But to notice we have to overcome our ingrained cultural biases. . . . Clearly, we will never play chess with a rose, nor ask the orchid on our windowsill for advice. But that is the point: humans are guilty of serious parochialism, of defining intelligence in terms of a nervous system and muscle-based speed that enables things to be done fast…Plants are highly responsive, attuned to gravity, grains of sand, sunlight, starlight, the footfalls of tiny insects, and to slow rhythms outside our range. They are subtle, aware, strategic beings whose lives involve an environmental sensitivity very distant from the simple flower and seed factories of popular imagination.”
Barnett praised Karban's book as a “timely, highly accessible summary of fast-developing fields.”
Karban is a fellow of the American Association for the Advancement of Science (AAAS) and has published more than 100 journal articles and now, three books.
Karban is featured in the Dec. 23-30, 2013 edition of The New Yorker in Michael Pollan's piece, “The Intelligent Plant: Scientists Debate a New Way of Understanding Plants."